introduce Account.get_blocked_contacts

also introduce Contact.block() and Contact.unblock() methods
and deprecate the c-ish "Contact.set_blocked()" api.
fixes #2011

python/src/deltachat/account.py

@@ -263,6 +263,17 @@ class Account(object):
         """
         return Contact(self, contact_id)
 
+    def get_blocked_contacts(self):
+        """ return a list of all blocked contacts.
+
+        :returns: list of :class:`deltachat.contact.Contact` objects.
+        """
+        dc_array = ffi.gc(
+            lib.dc_get_blocked_contacts(self._dc_context),
+            lib.dc_array_unref
+        )
+        return list(iter_array(dc_array, lambda x: Contact(self, x)))
+
     def get_contacts(self, query=None, with_self=False, only_verified=False):
         """ get a (filtered) list of contacts.
 

python/src/deltachat/contact.py

@@ -52,9 +52,17 @@ class Contact(object):
         return lib.dc_contact_is_blocked(self._dc_contact)
 
     def set_blocked(self, block=True):
-        """ Block or unblock a contact. """
+        """ [Deprecated, use block/unblock methods] Block or unblock a contact. """
         return lib.dc_block_contact(self.account._dc_context, self.id, block)
 
+    def block(self):
+        """ Block this contact. Message will not be seen/retrieved from this contact. """
+        return lib.dc_block_contact(self.account._dc_context, self.id, True)
+
+    def unblock(self):
+        """ Unblock this contact. Messages from this contact will be retrieved (again)."""
+        return lib.dc_block_contact(self.account._dc_context, self.id, False)
+
     def is_verified(self):
         """ Return True if the contact is verified. """
         return lib.dc_contact_is_verified(self._dc_contact)